Efficient treatment of ammonia-nitrogen contaminated waters by nano zero-valent iron/zeolite composite

Chemosphere ◽  
2021 ◽  
pp. 131990
Author(s):  
Osama Eljamal ◽  
Ramadan Eljamal ◽  
Ibrahim Maamoun ◽  
Ahmed M.E. Khalil ◽  
Tamer Shubair ◽  
...  
Molecules ◽  
2019 ◽  
Vol 25 (1) ◽  
pp. 47 ◽  
Author(s):  
Chunlei Jiao ◽  
Xiao Tan ◽  
Aijun Lin ◽  
Wenjie Yang

Nanometer zero-valent iron (nZVI) has been widely used in the treatment of heavy metals such as hexavalent chromium (Cr(VI)). A novel composite of bead string-structured nZVI on modified activated carbon (nZVI–MAC) is prepared here, using polyethylene glycol as the stable dispersant rather than traditional ethanol during the loading process. The microstructure characterization shows that nZVI particles are loaded on MAC with a bead string structure in large quantity and stably due to the addition of hydroxyl functional groups on the surface by polyethylene glycol. Experiments on the treatment of Cr(VI) in wastewater show that the reaction process requires only 20 min to achieve equilibrium. The removal rate of Cr(VI) with a low concentration (80–100 mg/L) is over 99% and the maximum saturation removal capacity is up to 66 mg/g. The system converts Cr(VI) to trivalent chromium (Cr(III)) through an oxidation-reduction effect and forms an insoluble material with iron ions by coprecipitation, which is then adsorbed on the surface of the nZVI–MAC. The process conforms to the quasi-second order adsorption kinetics equation (mainly chemical adsorption process).


2018 ◽  
Vol 5 (2) ◽  
pp. 88-101
Author(s):  
Nivedita Shukla ◽  
Amit Saxena ◽  
Vatsana Gupta ◽  
Ashok Singh Rawat ◽  
Sarita Shrivastava ◽  
...  

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2559
Author(s):  
Maja Radziemska ◽  
Zygmunt M. Gusiatin ◽  
Jiri Holatko ◽  
Tereza Hammerschmiedt ◽  
Andrzej Głuchowski ◽  
...  

In recent years, a lot of attention has been given to searching for new additives which will effectively facilitate the process of immobilizing contaminants in the soil. This work considers the role of the enhanced nano zero valent iron (nZVI) strategy in the phytostabilization of soil contaminated with potentially toxic elements (PTEs). The experiment was carried out on soil that was highly contaminated with PTEs derived from areas in which metal waste had been stored for many years. The plants used comprised a mixture of grasses—Lolium perenne L. and Festuca rubra L. To determine the effect of the nZVI on the content of PTEs in soil and plants, the samples were analyzed using flame atomic absorption spectrometry (FAAS). The addition of nZVI significantly increased average plant biomass (38%), the contents of Cu (above 2-fold), Ni (44%), Cd (29%), Pb (68%), Zn (44%), and Cr (above 2-fold) in the roots as well as the soil pH. The addition of nZVI, on the other hand, was most effective in reducing the Zn content of soil when compared to the control series. Based on the investigations conducted, the application of nZVI to soil highly contaminated with PTEs is potentially beneficial for the restoration of polluted lands.


Sign in / Sign up

Export Citation Format

Share Document